And tonight, a close call at one of the nation's busiest air ports has a lot of people looking at a new danger in the sky. Anyone in the country can buy a small, remote controlled drone. They're soaring in popularity. But what happens if a passenger plane has to dodge one on landing? Here's abc's david kerley. Reporter: It's never happened before. Five miles from a new york airport, a jumbo jet pilot suddenly spots something on final approach. Kennedy tower, just for your information, we just saw a little drone below us. Reporter: The alitalia pilot says the small, black, four rotor craft was within 200 feet of his jet. What altitude do you see that aircraft? About 1,500. Reporter: The fbi is on the case. It's an incident that frightens pilots. A couple of pounds hitting an airplane going 200, 250 miles per hour, if it hits the wrong place, like coming through the cockpit, hits the glass, it can hit the pilot or the co-pilot. It can hit an injengine, take out an engine. Reporter: You may think military, overseas and kill strikes when you heard the word drones. But these unmanned aircraft are showing up in american skies. Police departments are using small hand launched drones to look for suspects or missing children. But it's not just the government buying drones. Remote controlled aircraft, some toys, have been on the market for years. But look at what we bought at a hobby store for $700. This is the phantom. It is a drone, four rotors, it can carry a camera and go 22 miles an hour and 1,000 feet into the air. That's almost as high as the empire state building. But flying this drone above 400 feet within three miles of an airport violates federal guidelines, possibly even the law. With technology improving and prices dropping, the government worries many more will be taking off. New rules are being considered, but with drones easily available, will those rules be enough to keep our skies safe? David kerley, abc news, washington.

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